using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tango.BL.Entities;
using Tango.BL.Enumerations;
using Tango.PMR.Diagnostics;

namespace Tango.MachineStudio.Common.EventLogging
{
    /// <summary>
    /// Represents a database events logger.
    /// </summary>
    public interface IEventLogger
    {
        /// <summary>
        /// Occurs when a new machine event has been logged.
        /// </summary>
        event EventHandler<MachinesEvent> NewLog;

        /// <summary>
        /// Gets or sets a value indicating whether to save the incoming events to database.
        /// </summary>
        bool SaveToDB { get; set; }

        /// <summary>
        /// Logs the specified machine event.
        /// </summary>
        /// <param name="machineEvent">The machine event.</param>
        void Log(MachinesEvent machineEvent);

        /// <summary>
        /// Logs the specified event type.
        /// </summary>
        /// <param name="eventType">Type of the event.</param>
        /// <param name="message">The message.</param>
        void Log(EventTypes eventType, String message, bool write_to_db = true);

        /// <summary>
        /// Logs the specified hardware event.
        /// </summary>
        /// <param name="hardwareEvent">The hardware event.&l
using LiveCharts;
using LiveCharts.Wpf;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Media;
using Tango.BL.Enumerations;
using Tango.MachineStudio.Common;
using Tango.MachineStudio.Statistics.Models;
using Tango.BL.Entities;
using Tango.SharedUI;
using Tango.BL;
using Tango.MachineStudio.Common.Notifications;
using System.Threading.Tasks;
using Tango.Core.Commands;

namespace Tango.MachineStudio.Statistics.ViewModels
{
    public class ChartsViewVM : ViewModel
    {
        private INotificationProvider _notification;
        //private ObservablesContext _context;
        private List<JobRunStatisticsModel> _job_runs;
        private bool _loaded;

        #region Properties
        private LabeledSeriesCollection _timelineJobStatusSeries;
        public LabeledSeriesCollection TimelineJobStatusSeries
        {
            get { return _timelineJobStatusSeries; }
            set { _timelineJobStatusSeries = value; RaisePropertyChangedAuto(); }
        }

        private LabeledSeriesCollection _pieJobFailedReasons;
        public LabeledSeriesCollection PieJobFailedReasons
        {
            get { return _pieJobFailedReasons; }
            set { _pieJobFailedReasons = value; RaisePropertyChangedAuto(); }
        }

        private LabeledSeriesCollection _printPerWeekSeries;
        public LabeledSeriesCollection PrintPerWeekSeries
        {
            get { return _printPerWeekSeries; }
            set { _printPerWeekSeries = value; RaisePropertyChangedAuto(); }
        }

        private DateTime _startDate;
        public DateTime StartDate
        {
            get { return _startDate; }
            set { _startDate = value; RaisePropertyChangedAuto(); RaisePropertyChanged("EndDate"); }
        }

        private DateTime _endDate;
        public DateTime EndDate
        {
            get { return _endDate; }
            set { _endDate = value; RaisePropertyChangedAuto(); RaisePropertyChanged("StartDate"); }
        }
        
        public RelayCommand LoadJobRunsCommand { get; set; }
        #endregion

        public ChartsViewVM(INotificationProvider notificationProvider)
        {
            _notification = notificationProvider;
            StartDate = DateTime.Now.AddMonths(-1);
            EndDate = DateTime.Now;
            LoadJobRunsCommand = new RelayCommand(async () => await LoadJobRuns(), () => IsFree);
        }

        #region Generate Charts
        
        private async Task LoadJobRuns()
        {
            using (_notification.PushTaskItem("Loading statistics..."))
            {
                try
                {
                    IsFree = false;
                    
                    await Task.Factory.StartNew(() =>
                    {
                        using (var db = ObservablesContext.CreateDefault())
                        {
                            DateTime startUtc = new DateTime(StartDate.Year, StartDate.Month, StartDate.Day, 0, 0, 0).ToUniversalTime();
                            TimeSpan offsetTime = (EndDate.Date == DateTime.Now.Date) ? DateTime.Now.TimeOfDay : new TimeSpan(23, 59, 59);
                            DateTime endUtc = EndDate.ToUniversalTime() + offsetTime;
                            
                            _job_runs = db.JobRuns.Where(x => (x.StartDate <= endUtc && x.StartDate >= startUtc)).OrderBy(x => x.StartDate).ToList().Select(x => new JobRunStatisticsModel(x)).ToList();
                        
                            foreach (var run in _job_runs)
                            {
                                run.LoadMachine(db).GetAwaiter().GetResult();
                            }
                        }
                    });
                    
                    InvokeUIOnIdle(() =>
                    {
                        if (_loaded)
                        {
                            OnDateRangeChanged();
                        }
                    });

                    _loaded = true;
                }
                catch (Exception ex)
                {
                    LogManager.Log(ex, "Error loading statistics.");
                }
                finally
                {
                    IsFree = true;
                }
            }
        }


        private List<JobRunStatisticsModel> GetJobRunsByDateRange(DateTime startDate, DateTime endTime, JobRunStatus? status = null)
        {
            return _job_runs.Where(x => x.StartDate.ToLocalTime() >= startDate && x.StartDate.ToLocalTime() <= endTime && (status == null || x.JobRunStatus == status)).ToList();
        }

        private List<JobRunStatisticsModel> GetJobRunsByDate(DateTime date, JobRunStatus? status = null)
        {
            return _job_runs.Where(x => x.StartDate.ToLocalTime().Date == date.Date && (status == null || x.JobRunStatus == status)).ToList();
        }

        private IEnumerable<DateTime> CreateDates(DateTime start, DateTime end)
        {
            for (DateTime date = start.Date; date.Date <= end.Date; date = date.AddDays(1))
            {
                yield return date;
            }
        }
        
        private void GenerateTimelineJobStatusChart()
        {
            TimelineJobStatusSeries = new LabeledSeriesCollection()
            {
                Title = "Job Runs Status",
                ChartTitle = "Number Of Runs",
                LabelsTitle = "Date",
                SeriesColors = new List<Color>()
                    {
                         Colors.Green,
                         Colors.Orange,
                         Colors.Red,
                    },
            };

            Series completed_job_runs = new ColumnSeries()
            {
                Title = "Completed",
                Values = new ChartValues<int>(),
                Fill = Brushes.Green,
                MinWidth = 1,

            };
            Series aborted_job_runs = new ColumnSeries()
            {
                Title = "Aborted",
                Values = new ChartValues<int>(),
                Fill = Brushes.Orange,
                MinWidth = 1,
            };
            Series failed_job_runs = new ColumnSeries()
            {
                Title = "Failed",
                Values = new ChartValues<int>(),
                Fill = Brushes.Red,
                MinWidth = 1,
            };

            if (EndDate - StartDate > TimeSpan.FromDays(40))
            {
                completed_job_runs = new LineSeries()
                {
                    Title = "Completed",
                    Values = new ChartValues<int>(),
                    Fill = new SolidColorBrush(Colors.Green) { Opacity = 0.5 },
                    MinWidth = 1,
                    PointGeometry = null,
                    StrokeThickness = 0,

                };
                aborted_job_runs = new LineSeries()
                {
                    Title = "Aborted",
                    Values = new ChartValues<int>(),
                    Fill = new SolidColorBrush(Colors.Orange) { Opacity = 0.5 },
                    MinWidth = 1,
                    PointGeometry = null,
                    StrokeThickness = 0,
                };
                failed_job_runs = new LineSeries()
                {
                    Title = "Failed",
                    Values = new ChartValues<int>(),
                    Fill = new SolidColorBrush(Colors.Red) { Opacity = 0.5 },
                    MinWidth = 1,
                    PointGeometry = null,
                    StrokeThickness = 0,
                };
            }

            foreach (var date in CreateDates(StartDate, EndDate))
            {
                completed_job_runs.Values.Add(GetJobRunsByDate(date, JobRunStatus.Completed).Count());
                aborted_job_runs.Values.Add(GetJobRunsByDate(date, JobRunStatus.Aborted).Count());
                failed_job_runs.Values.Add(GetJobRunsByDate(date, JobRunStatus.Failed).Count());

                TimelineJobStatusSeries.Labels.Add(date.ToShortDateString());
            }



            TimelineJobStatusSeries.SeriesCollection.Add(failed_job_runs);
            TimelineJobStatusSeries.SeriesCollection.Add(aborted_job_runs);
            TimelineJobStatusSeries.SeriesCollection.Add(completed_job_runs);
        }

        private void GeneratePieFailedReasonsChart()
        {
            var groups = GetJobRunsByDateRange(StartDate, EndDate, JobRunStatus.Failed).GroupBy(x => x.FailedMessage).OrderBy(x => x.Count());

            List<Color> colors = new List<Color>();

            int max = groups.Count() > 0 ? groups.Max(x => x.Count()) : 0;

            for (int i = 0; i < groups.Count(); i++)
            {
                int count = groups.ElementAt(i).Count();
                double alpha = Math.Max(((double)(count) / max * 200), 20);
                colors.Add(Color.FromArgb((byte)alpha, 200, 0, 0));
            }

            PieJobFailedReasons = new LabeledSeriesCollection()
            {
                Title = "Job Failure Reasons",
                SeriesColors = colors,
            };

            int index = 0;

            foreach (var group in groups)
            {
                int count = group.Count();

                var series = new PieSeries()
                {
                    Title = group.First().FailedMessage,
                    Values = new ChartValues<int>() { count },
                    Fill = new SolidColorBrush(colors[index++]),
                    DataLabels = true,
                    ToolTip = group.First().FailedMessage,
                };

                PieJobFailedReasons.SeriesCollection.Add(series);
            }
        }

        private void GeneratePrintPerWeekChart()
        {
            List<JobRunStatisticsModel> range_job_runs = GetJobRunsByDateRange(StartDate, EndDate);

            Dictionary<Machine, List<double>> weeks_print_avg = new Dictionary<Machine, List<double>>();

            //Init machines weeks averages dictionary.
            foreach (var machine in range_job_runs.Select(x => x.Machine).OrderBy(x => x.Name).DistinctBy(x => x.Guid))
            {
                weeks_print_avg[machine] = new List<double>();
            }

            //Create all available dates
            List<DateTime> all_dates = range_job_runs.Select(x => x.StartDate).ToList();

            //get first Sunday.
            DateTime current_sunday = all_dates.FirstOrDefault(x => x.DayOfWeek == DayOfWeek.Sunday);

            if (current_sunday != null && all_dates.Count > 0)
            {
                //Iterate over each week starting from the earliest Sunday.
                while (current_sunday <= all_dates.Last())
                {
                    var week_job_runs = range_job_runs.Where(x => x.EndPosition > 10 && x.StartDate >= current_sunday && x.StartDate <= current_sunday.AddDays(7)).ToList();

                    foreach (var machine_job_runs in week_job_runs.GroupBy(x => x.Machine))
                    {
                        weeks_print_avg[machine_job_runs.Key].Add(machine_job_runs.Select(x => x.EndPosition).Average());
                    }

                    current_sunday = current_sunday.AddDays(8);
                }
            }

            Dictionary<Machine, double> week_print_avg = new Dictionary<Machine, double>();

            //Init machines week average dictionary.
            foreach (var machine in weeks_print_avg)
            {
                if (machine.Value.Count > 0)
                {
                    week_print_avg[machine.Key] = machine.Value.Average();
                }
            }

            //Init chart series
            PrintPerWeekSeries = new LabeledSeriesCollection()
            {
                Title = "Average Printed Thread Per Week (m)",
                ChartTitle = "Average Print Per Week (m)",
                LabelsTitle = "Date",
                SeriesColors = new List<Color>()
                {

                },
            };

            //Init series colors intensity by number of prints.
            double max = week_print_avg.Count > 0 ? week_print_avg.Max(x => x.Value) : 0;
            foreach (var machine in week_print_avg)
            {
                double a = (machine.Value / max);
                PrintPerWeekSeries.SeriesColors.Add(Color.FromArgb((byte)(255d * (machine.Value / max)), 0, 200, 0));
            }

            //Init columns.
            int index = 0;

            foreach (var machine in week_print_avg)
            {
                var series = new ColumnSeries()
                {
                    Title = machine.Key.Name,
                    Values = new ChartValues<int>() { (int)machine.Value },
                    Fill = new SolidColorBrush(PrintPerWeekSeries.SeriesColors[index++]),
                    DataLabels = true,
                    ToolTip = machine.Key.SerialNumber,
                };

                PrintPerWeekSeries.SeriesCollection.Add(series);
            }
        }

        #endregion

        #region Filter by Date
        public void OnDateRangeChanged()
        {
            if (_job_runs != null)// && _job_runs.Count > 0)// && _loaded)
            {
                GenerateTimelineJobStatusChart();
                GeneratePieFailedReasonsChart();
                GeneratePrintPerWeekChart();
            }
        }
        #endregion
        
    }
}